Flooding, debris flows, thunderstorms, hail and even small tornados could all be on the horizon across the Southern California region as a storm system prepares to dump two rounds of sometimes heavy rain on the area, prompting evacuation warnings for residents near recent burn areas.
National Weather Service forecasters said at least 3 to 6 inches of rain are anticipated across the region, with the bulk of the precipitation expected late Friday into Saturday, and mountain areas likely to receive the biggest dose of wet weather.
The “first band” of rain is not expected to reach Los Angeles County until Friday. That first band is expected to be the weaker of the two approaching systems, with forecasters saying they are “not expecting any significant issues other than some wet roadways” on Friday.
The second wave of precipitation arriving Saturday “has the potential to be the most significant,” according to the NWS, which said some models show the potential for another 3-5 inches of rain just from the second band of precipitation alone.
“Forecast soundings from Santa Maria to Long Beach indicate favorable profiles for thunderstorms and severe weather, which would include a small chance of weak tornados, strong and gusty winds, very heavy rain (possibly even locally exceeding one inch per hour), and hail,” according to the NWS. “The ultimate path of the upper low will likely determine if and where these occur but for now they are all in play for all areas.”
A flood watch issued by the NWS will be in effect from late Friday night through Saturday evening for the entirety of Los Angeles County, along with most of Santa Barbara and Ventura counties.
“There will be breaks in the rainfall, sometimes for several hours and rainfall is expected to taper off by later Saturday night, assuming the upper low behaves and moves into Nevada Sunday afternoon, forecasters said. “Rain chances continue in the forecast through Sunday as many of the ensembles maintain enough low level moisture and instability to trigger some light precipitation but there should be no significant impacts after early Sunday morning.”
The city of Los Angeles issued an evacuation warning that’ll be in effect through 11 a.m. Sunday for residents near the Palisades, Hurst and Sunset fire burn zones. County officials issued an evacuation warning for residents near the Eaton Fire area in Altadena. County officials warned that any other recent burn areas could also be at increased risk of flooding or debris flows.
The city of Los Angeles’ Emergency Operations Center will activate at 6 p.m. Thursday and the mayor’s office stated that it will coordinate with the Emergency Management Department, Los Angeles Fire Department, Los Angeles Police Department, Los Angeles County Public Works and relevant city departments to ensure all personnel are ready to respond as needed to keep residents safe.
The county was offering residents free sandbags for pickup at the Public Works Fleet Maintenance Yard, 252 Mountain View St. in Altadena, and at the Malibu Library parking lot, 23519 W. Civic Center Way. The LAFD was providing free sandbags at fire stations throughout the city, with sand available at some of those locations. A listing of locations and more information is available at lafd.org/news/lafd-provides-sandbags-homeowners-1.
Gov. Gavin Newsom said the state was pre-deploying emergency response crews in Los Angeles, Orange and Ventura counties to enable faster response to any storm-related issues that develop. He said 274 personnel were being deployed, along with 18 engines, three Urban Search & Rescue companies, six bulldozers, three swiftwater-rescue teams, three helicopters and five dispatchers.
In the Palisades Fire area, Caltrans will close Topanga Canyon Boulevard between Pacific Coast Highway and Grand View Drive at 10 p.m. Thursday. Caltrans officials said motorists should expect the stretch to remain closed at least through the Friday morning commute, but potentially through the weekend, depending how the storm develops.
That stretch of Topanga Canyon has been undergoing nightly repairs, with the road closed between midnight and 5 a.m.
NWS forecasters urged homeowners to prepare for the rain by ensuring gutters are cleared and windshield wipers are secure and working. They said people should consider rescheduling outdoor events, and advised motorists to avoid driving through flooded areas.
The Los Angeles County Sheriff’s Department issued a statement Wednesday urging people to be prepared, offering a series of tips:
— Drive carefully, slow down and allow extra stopping distance;
— avoid flooded roads, turn around, wait it out;
— prepare your property by gathering sand bags, and checking gutters and drains; and
— check the condition of your vehicle and replace windshield wipers and tires if needed.
Sheriff’s officials urged people to use websites like Ready.Lacounty.gov to stay up to date on road closures, weather alerts, and emergency notifications.
“Our deputies will be out monitoring conditions and ensuring community safety,” according to the department. “Let’s all do our part to stay safe during the storm.”